Hi guys,

I'm trying to create a website that revolves around business listings. What I'm trying to do is find all the companies that have offices in given city/state. What would be the most effective way to find companies?

So say for example I wanted to know all the companies in Phoenix AZ that developed software. Now I would also like to take into account companies that are global. Like IBM, GE, Intel ect. So if IBM had an office in Phoenix AZ I'd like have that branch pop up in the search. After I get the listing I'd like to have them all put into one file so I can update the website.

I did think about using phone books, searches through like switchboard.com but those return companies like Radio Shack or other companies that have stores there but they're not developing software. So it doesn't really work that well.

I was thinking of a web crawler maybe but I haven't found one that I liked. Any ideas?